Are replacement O-rings available for the plugs? Yes.  They are Item #3041.  We also recommend purchasing a tube of ELEY Silicone Grease, which is designed explicitly for our O-ring material. Periodically applying a thin coating of this 100% silicone grease to the O-rings will extend their life and improve performance. Does the socket stop the water flow when I remove the plug from it? No.  The plug cannot be removed while under pressure.  The water pressure must be first turned off before the quick-connect set can be separated.  There are two methods of doing this.  First, by shutting the water off back at the faucet/water source.  The second method is to install a ball valve directly before the socket. (See photo) This will allow you to shut the water off right at the quick-connect set, without having to return to the faucet/water source. Eley offers two garden hose ball valves that work perfectly for this application, our straight Garden Hose Ball Valve and our Swivel Garden Hose Ball Valve. How will these perform in freezing temperatures? You'll likely have some difficulty.  Even with water flowing in freezing environments, it doesn't take much moisture to cause the brass parts to stick together. In particular, it may be challenging to get the sleeve on the socket to slide to disengage the plug.  The quick-connect sets were designed to operate in above freezing conditions. Is this item drinking water safe? Yes.  Water flowing through your ELEY reels, hoses, and watering tools stays pure because we use only 100% drinking water-safe internal component materials. It's all safe from the lead-free brass and rubber seals down to the assembly lube. Are they compatible with other brands of quick-connectors? No.  What maintenance is required? Depending on the frequency of use, the O-rings on the plugs should periodically be coated with a thin layer of Silicone Grease. This will not only improve the performance of the quick-connect set but also increase the life of the O-rings.